Mini Amplifier Circuit

Audio amplifiers are electronic amplifiers that are used to amplify weak audio signals from an input like a mic to high amplitude signals to be reproduced through loudspeakers.

This is a very simple hobby project suitable for beginners. This homemade mini amplifier circuit is suitable to hone your soldering skills and show off in front of not so electronic savvy friends.

Description

Here is a simple and humble 2 Watts mini audio amplifier circuit suitable for small pocket radios and other portable audio gadgets. The circuit is based on Phillips Semiconductors IC TDA 7052. The amplifier can be run even from a 3V Mercury button cell. This makes it ideal for battery operated gadgets.

The IC TDA7052 is a mono output amplifier coming in a 8-lead DI package (DIP). The device is mainly designed for battery-operated portable audio circuits. The features of TDA 7052 include; no external components needed, no switch-on or switch-off click sounds , great overall stability, very low power consumption(quiescent current 4mA) , low THD, no heat sinks required and short-circuit proof.

The gain of TDA 7052 is fixed internally at 40 dB. To compensate the reduction of output power due to low voltage supply the TDA7052 uses the Bridge-Tied-Load principle
(BTL) which can provide an output of around 1 to 2 W Rms(THD = 10%) into an 8 Ohm load with a power supply of 6 V.

In the circuit, the potentiometer can be used to control the volume. Capacitor C1 and C2 are meant for filtering the supplyvoltage if a battery eliminator is used as a supply source. For operations using a battery C1 and C2 are no necessary.

Mini Audio Amplifier Circuit Diagram with Parts List

Mini Audio Amplifier Circuit Diagram

Audio input – 1 nos

Potentiometer – 1 nos

Capacitor 220uF – 1 nos

Capacitor 100nF – 1 nos

IC TDA 7052 – 1 nos

Power source – 6 V

Output speaker – 1 nos

Notes.

Assemble the circuit on a good quality PCB or common board .

If you are a little expert, you can assemble the circuit in a match box including the speaker.

Comments

Hi, thanks for u r reply in main operated led. now I would like to use this circuit as a amp for my android phone, is it safe? and how to fed the stereo? and if I use a 1w 4ohm speaker.
thanx in advance

Hi Chetan the recommended volltage is 6 volt only for the above operation (in BTL mode, ensure that you use only 8 ohms speaker. Hope you are using screened wire for input. Still if you have problem due to may poor layout, you can add a 470 pf ceramic disc capacitor between Pin2 & 3 of IC.

Hi Chetan connect load through 4nos IN4007 diodes in series in the positive line connect negative line direct. these diodes will drop around 2.8 volts. these diodes will be ok upto 1 amp load if more you want use suitable current rated diodes.
Hope you are happy with the amplifier.

Hi Steven you can use 4 ohms speaker with which you will get 1.2watt RMS, the most efficient operating zone of the IC.
Hi Sqirrel Though the IC can handle up to 18 volts with 6 volts in BTL mono operation it gives the best performance, and very safe to operate also. please refer to philips manual. 1.2 watts power is quite adequate for listening in a quite room.

hi there..can you help me with this one..the sound is very weak..i can’t hear the music..is it possible to use 8ohm 0.3w speaker??but I tested the speaker on a device and it works perfectly..maybe my problem is the connection on the audio in..the 3.5mm audio plug..